A major leader in the Tea Party movement was arrested at New York's LaGuardia Airport on Thursday after he tried to check in for a flight while carrying a gun.

Prosecutors charged Mark Meckler, the co-founder of Tea Party Patriots, with felony weapons possession after he told a Delta ticket agent early Thursday morning that he had a weapon in his luggage.

Meckler was carrying an unloaded Glock pistol and numerous rounds of ammunition in a locked gun box, according to multiple reports.

Meckler’s attorney, Brian Stapleton, said Meckler had a concealed-carry permit for the gun issued by California, and that Meckler was in temporary transit through New York.

But the California permit wasn’t valid in New York.

“He legally declared his possession of the firearm in his checked baggage at the ticket counter as required by law and in a manner approved by TSA and the airline, yet was arrested by port authority for said possession,” Stapleton said in a statement.

Under New York law, Meckler could face up to 15 years in prison if found guilty of the charge.